CD74ACT157
QUADRUPLE 2-LINE TO 1-LINE DATA SELECTOR/MULTIPLEXER
SCHS340B MARCH 2003 - REVISED JUNE 2003
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
D
Inputs Are TTL-Voltage Compatible
D
Speed of Bipolar F, AS, and S, With
Significantly Reduced Power Consumption
D
Balanced Propagation Delays
D
24-mA Output Drive Current
Fanout to 15 F Devices
D
SCR-Latchup-Resistant CMOS Process and
Circuit Design
D
Exceeds 2-kV ESD Protection Per
MIL-STD-883, Method 3015
description/ordering information
This quadruple 2-line to 1-line data selector/multiplexer is designed for 4.5-V to 5.5-V V
CC
operation.
The CD74ACT157 features a common strobe (G) input. When the strobe is high, all outputs are low. When the
strobe is low, a 4-bit word is selected from one of two sources and is routed to the four outputs. The device
provides true data.
ORDERING INFORMATION
TA
PACKAGE
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
55 C to 125 C
PDIP E
Tube
CD74ACT157E
CD74ACT157E
55 C to 125 C
SOIC M
Tube
CD74ACT157M
ACT157M
55
C to 125
C
SOIC M
Tape and reel
CD74ACT157M96
ACT157M
TSSOP PW
Tube
CD74ACT157PW
HM157
TSSOP PW
Tape and reel
CD74ACT157PWR
HM157
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines
are available at www.ti.com/sc/package.
FUNCTION TABLE
INPUTS
OUTPUT
G
A/B
A
B
OUTPUT
Y
H
X
X
X
L
L
L
L
X
L
L
L
H
X
H
L
H
X
L
L
L
H
X
H
H
Copyright
2003, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
A /B
1A
1B
1Y
2A
2B
2Y
GND
V
CC
G
4A
4B
4Y
3A
3B
3Y
E, M, OR PW PACKAGE
(TOP VIEW)
CD74ACT157
QUADRUPLE 2-LINE TO 1-LINE DATA SELECTOR/MULTIPLEXER
SCHS340B MARCH 2003 - REVISED JUNE 2003
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
logic diagram (positive logic)
2
3
5
6
11
10
14
13
15
1
G
A/B
4B
4A
3B
3A
2B
2A
1B
1A
4
7
9
12
1Y
2Y
3Y
4Y
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage range, V
CC
0.5 V to 6 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input clamp current, I
IK
(V
I
< 0 V or V
I
> V
CC
)
(see Note 1)
20 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output clamp current, I
OK
(V
O
< 0 V or V
O
> V
CC
)
(see Note 1)
50 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous output current, I
O
(V
O
> 0 V or V
O
< V
CC
)
50 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous current through V
CC
or GND
100 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Package thermal impedance,
JA
(see Note 2): E package
67
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
M package
73
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PW package
108
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
65
C to 150
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES:
1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
2. The package thermal impedance is calculated in accordance with JESD 51-7.
CD74ACT157
QUADRUPLE 2-LINE TO 1-LINE DATA SELECTOR/MULTIPLEXER
SCHS340B MARCH 2003 - REVISED JUNE 2003
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
recommended operating conditions (see Note 3)
TA = 25
C
55
C to
125
C
40
C to
85
C
UNIT
MIN
MAX
MIN
MAX
MIN
MAX
UNIT
VCC
Supply voltage
4.5
5.5
4.5
5.5
4.5
5.5
V
VIH
High-level input voltage
2
2
2
V
VIL
Low-level input voltage
0.8
0.8
0.8
V
VI
Input voltage
0
VCC
0
VCC
0
VCC
V
VO
Output voltage
0
VCC
0
VCC
0
VCC
V
IOH
High-level output current
24
24
24
mA
IOL
Low-level output current
24
24
24
mA
t/
v
Input transition rise or fall rate
10
10
10
ns/V
NOTE 3: All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
VCC
TA = 25
C
55
C to
125
C
40
C to
85
C
UNIT
PARAMETER
TEST CONDITIONS
VCC
MIN
MAX
MIN
MAX
MIN
MAX
UNIT
V
V = V
or V
IOH = 50
A
4.5 V
4.4
4.4
4.4
V
VOH
VI = VIH or VIL
IOH = 24 mA
4.5 V
3.94
3.7
3.8
V
VOH
VI = VIH or VIL
IOH = 50 mA
5.5 V
3.85
V
IOH = 75 mA
5.5 V
3.85
V
V = V
or V
IOL = 50
A
4.5 V
0.1
0.1
0.1
V
VOL
VI = VIH or VIL
IOL = 24 mA
4.5 V
0.36
0.5
0.44
V
VOL
VI = VIH or VIL
IOL = 50 mA
5.5 V
1.65
V
IOL = 75 mA
5.5 V
1.65
II
VI = VCC or GND
5.5 V
0.1
1
1
A
ICC
VI = VCC or GND,
IO = 0
5.5 V
8
160
80
A
D
ICC
VI = VCC 2.1 V
4.5 V to 5.5 V
2.4
3
2.8
mA
Ci
10
10
10
pF
Test one output at a time, not exceeding 1-second duration. Measurement is made by forcing indicated current and measuring voltage to minimize
power dissipation. Test verifies a minimum 50-
transmission-line drive capability at 85
C and 75-
transmission-line drive capability at 125
C.
Additional quiescent supply current per input pin, TTL inputs high, 1 unit load
ACT INPUT LOADING TABLE
INPUT
UNIT LOAD
A or B
0.37
G
0.83
A/B
1.33
Unit load is
ICC limit specified in
electrical characteristics table
(e.g., 2.4 mA at 25
C).
CD74ACT157
QUADRUPLE 2-LINE TO 1-LINE DATA SELECTOR/MULTIPLEXER
SCHS340B MARCH 2003 - REVISED JUNE 2003
4
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
switching characteristics over recommended operating free-air temperature range,
V
CC
= 5 V
0.5 V, C
L
= 50 pF (unless otherwise noted) (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
55
C to
125
C
40
C to
85
C
UNIT
PARAMETER
(INPUT)
(OUTPUT)
MIN
MAX
MIN
MAX
UNIT
tPLH
A or B
Any Y
2.4
9.5
2.5
8.6
ns
tPHL
A or B
Any Y
2.4
9.5
2.5
8.6
ns
tPLH
A/B
Any Y
3.6
14.5
3.8
13.2
ns
tPHL
A/B
Any Y
3.6
14.5
3.8
13.2
ns
tPLH
G
Any Y
3.4
13.5
3.6
12.3
ns
tPHL
G
Any Y
3.4
13.5
3.6
12.3
ns
operating characteristics, V
CC
= 5 V, T
A
= 25
C
PARAMETER
TYP
UNIT
Cpd
Power dissipation capacitance
156
pF
CD74ACT157
QUADRUPLE 2-LINE TO 1-LINE DATA SELECTOR/MULTIPLEXER
SCHS340B MARCH 2003 - REVISED JUNE 2003
5
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
PARAMETER MEASUREMENT INFORMATION
VOLTAGE WAVEFORMS
SETUP AND HOLD AND INPUT RISE AND FALL TIMES
th
tsu
10%
10%
90%
90%
3 V
3 V
0 V
0 V
tr
tf
Reference
Input
Data
Input
VOLTAGE WAVEFORMS
PROPAGATION DELAY AND OUTPUT TRANSITION TIMES
50% VCC
50%
10%
10%
90%
90%
3 V
VOH
VOL
0 V
tr
tf
Input
In-Phase
Output
tPLH
tPHL
50% VCC
50%
10%
10%
90%
90%
VOH
VOL
tr
tf
tPHL
tPLH
Out-of-Phase
Output
NOTES: A. CL includes probe and test-fixture capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. All input pulses are supplied by generators having the following characteristics: PRR
1 MHz, ZO = 50
, tr = 3 ns, tf = 3 ns.
Phase relationships between waveforms are arbitrary.
D. For clock inputs, fmax is measured with the input duty cycle at 50%.
E. The outputs are measured one at a time with one input transition per measurement.
F. tPLH and tPHL are the same as tpd.
G. tPZL and tPZH are the same as ten.
H. tPLZ and tPHZ are the same as tdis.
I. All parameters and waveforms are not applicable to all devices.
From Output
Under Test
CL = 50 pF
(see Note A)
LOAD CIRCUIT
S1
2
VCC
R1 = 500
Open
GND
0 V
tw
VOLTAGE WAVEFORMS
PULSE DURATION
Input
3 V
tPLH/tPHL
tPLZ/tPZL
tPHZ/tPZH
Open
2
VCC
GND
TEST
S1
Output
Control
Output
Waveform 1
S1 at 2
VCC
(see Note B)
Output
Waveform 2
S1 at GND
(see Note B)
VOL
VOH
tPZL
tPZH
tPLZ
tPHZ
VCC
0 V
20% VCC
20% VCC
80% VCC
0 V
VOLTAGE WAVEFORMS
OUTPUT ENABLE AND DISABLE TIMES
80% VCC
3 V
R2 = 500
VOLTAGE WAVEFORMS
RECOVERY TIME
3 V
0 V
CLR
Input
CLK
3 V
trec
0 V
1.5 V
1.5 V
1.5 V
1.5 V
1.5 V
1.5 V
1.5 V
1.5 V
1.5 V
1.5 V
1.5 V
Figure 1. Load Circuit and Voltage Waveforms
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